1. Field
The present disclosure relates to a porous material, and in particular relates to a porous carbon material and manufacturing methods thereof, and a supercapacitor using the same.
2. Description of the Related Art
Supercapacitors represent revolutionary developments in energy storage, and may replace traditional storage batteries in certain fields in the future. The supercapacitor is a new energy storage device that exists due to advancements in material science. The supercapacitor is a new electrochemical device, which stores electrical energy via the polarization between an electrolytic solution and the surface of a carbon electrode. The global need for supercapacitors has risen quickly since commercial market availability, and they have become a new superstar in the field of electrochemical power. The supercapacitor has a huge application value and market potential in such applications as electric vehicles, mixed-fuel vehicles, exceptional-load vehicles, electrical power, railroads, communication, national defense, and consumer electronic products.
The supercapacitor has the advantages of having a high charge-discharge speed, being pollution-free, and having a long cycle life, so the supercapacitor is regarded as a new type of green energy storage system for the present century. In view of the usage qualities of electrical power, the supercapacitor has many advantages over batteries, such as a higher output power (>10 kW/kg), higher charge-discharge efficiency, and longer cycle life (>200,000 times). The supercapacitor may raise the instantaneous power and may recharge during braking. In view of energy savings, the supercapacitor is an indispensable auxiliary energy source. Also, the characteristic high discharge speed of the supercapacitor means it can be used in uninterruptible power supplies, and the supercapacitor can provide electric energy immediately at the moment of a power failure to recover the essential response time of batteries.
In general, the electrode of a supercapacitor is mainly made of a porous structure, which may be of a micro- or nanometer scale with a large surface area used to produce an electric double layer of an electrostatic-charge storage device. Specifically, the supercapacitor stores electrical energy by directly forming electrostatic charges on the electrode plate of the capacitor, and this kind of charge storage is called non-Faradic which means that there is no electron transfer occurring on the interface of the electrode.
The present commercial supercapacitor is limited by the small specific surface area (500-1000 m2/g) of the carbon electrode material thereof, such that the energy density thereof is lower (<5 Wh/kg), and the electrical capacity thereof is around 5-35 F/g. A carbon electrode material that is highly porous and has a large surface area can effectively improve the total efficiency of the supercapacitor, but the present manufacturing method of this kind of carbon electrode material (referring TW patent NO. I274453) involves a long processing time (about 3-7 days) and high energy (a process temperature is 2000° C.).